local meta = FindMetaTable("Entity");

local validDoor = {
	"func_door",
	"func_door_rotating",
	"func_movelinear",
	"prop_door_rotating"
};

function meta:IsDoor()
	local class = self:GetClass();
	
	for i = 1, 4 do
		if (validDoor[i] != class) then continue; end;
		
		return true;
	end;
end;